When the sun goes down Wednesday, some of the metro area's most iconic buildings will turn bright blue.

At least a half a dozen Twin Cities' buildings and structures will take on a blue hue — including Capella Tower, Target headquarters, U.S. Bancorp, the Lowry Avenue Bridge and the Interstate 35W bridge in Minneapolis; 10 West End in St. Louis Park; Sperry Tower in Eagan and the billboard in CHS Field in St. Paul — in support of Angelman syndrome, a rare neurogenetic disorder.

Buildings in downtown are sometimes lit with colored lights to celebrate holidays or milestones or raise awareness. Capella Tower, for example, switched from its normal white lights to red, black, green and gold for the first day of Black History month (Feb. 1). It'll go to blue and gold on Feb. 24-26 to support Ukraine.

Angelman syndrome affects about 1 in 150,000, according to Meghan Edberg, director of community engagement for the Foundation for Angelman Syndrome Therapeutics (FAST), a parent-led advocacy organization launched in 2008.

Edberg, who is from Rosemount, joined the organization after her son, Will, now 5 years old, was diagnosed with Angelman syndrome. Her family has raised more than $500,000 in the last three years through their Will.i.CAN fundraiser.

Children and adults with the syndrome typically have substantial cognitive impairment, balance issues, motor impairment and can have seizures. Many cannot speak and have sleep difficulties, some never walk. The syndrome also can include a happy demeanor, characterized by frequent laughter, smiling, and excitability, according to FAST.

Buildings in the Twin Cities aren't the only ones lighting up for International Angelman Day. They'll join landmarks in Turkey, Canada, Philadelphia and Australia.

"We're thankful Minneapolis and St. Paul joined the awareness effort," said Edberg. "We want people to see the blue and learn more about Angelman and seek out how they can help."